Relativity : the Special and General Theory

The text introduces basic notions of space, time, and measurement and develops the special theory by examining simultaneity, coordinate systems, Lorentz transformations, and resulting effects such as time dilation and velocity addition, culminating in a four-dimensional spacetime view. It then formulates the general theory by presenting the equivalence of inertial and gravitational mass, a generalized relativity principle, and a geometric description of gravity using non-Euclidean spacetime and coordinate methods. Supplementary sections treat cosmological considerations, simple mathematical derivations, and empirical tests including the perihelion advance of Mercury, light deflection, and gravitational redshift.